Internal-combustion engine.



. G.- M. s.' T AIT se o. ELLIS.

` INTERNAL OOMBSTION ENGINE.

' AAPPLIOAflION IILED FEB. B, 1906.

Petem-,ed Feb.2,19o9.

s SHEETS-SHEET 2.

INVENTOR ATTORNE -G. M. S. TAIT & ELLIS.

INTERNAL GOMBUSI-ION ENGINE.

APPLIGATION FILED rma. a

Patented Feb. 2, 1909.

SHEETS-SHEET 3.

iNVENTORS ATTRNEY entre y L srairns 'fr enrich;

eopFREY M. s'. 'rArrfoF MONTLAIB, NEW JERSEY, AND oARLEToN ELLIS,OE'WHITEPLAINS,

i NEW YORK'.

INTERNAL-COMBUSTIONENGINE.

No. mns/i5.v

v Specication of Letters Patent. Appneaaon sled February 8,1996. serialNn. acoso?.

renteareb. a, i909.

To all whom it fmay concern:

Be it known that We', Gournay M. S. TAIT,

a British subject, residing in Montclair, Esf

sex county, New Jersey, and CARLnToN EL- Lis, residlng in White Plains,Vrestchester county, New York, have invented certain.

newand useful mprovements'in'internal- Combustion Engines, of which thefollowing is a specification. ,y w f Our invention relates toimprovements in internal -combustion l engines, and involves featuresparticularly valuable in engines intended to 'be operated by producergas and similar gas `of lov;r or Avariable thermal value or comprisinggaseous ingredients havin quite different properties as regardsseltignition, flame-propagation etc. The engine herein described carriesout the process of re ulating the development of power in internacombustion engines, forming the subject matter of the application forLetters Patent, 4filed by us on' November 14th, i905, Sr. No. 287,240.-f

Ourinvention consists in novel means for regulating the operation ofinternal confibust-ion engines; in improvements in the value gear andigniting gear, and in means.

for automatically ,y adjusting the same in accordance withvariation ofspeed of the engine, and in other features of invention, all ashereinafter described and particularly pointed out in the claims. y

The methods heretofore employed for regulating the operation of internalcombustion engines have all proved unsatisfactory. The liit-andmissmethod of` regulation produces excessive speed fluctuations, so that itis entirely im ract'ica-ble in many cases, and in many of it forms isextremelyl waste. -ful of' fuel. All jm'ethods of regulating in'-vvolving variation in the quantity of gas and air taken into thecylinder, suchl as' throtf tling andA variable opening or closing of theadmission valve (the latter-methodsomey times termed variable'cuto)4produce extreme variation in the compression pressure, suchv pressureincreasing at'fdifferent rates according-to- ,the quantity of gasand airtaken into the cylinder. i Such variation in compression is extremelydetrimental as regards economy,'for it is well known that for highestefficiency high `,compression is necessary, and obviously an enginewhich at light loads compresses only to relatively low pressures, isuneconomical at suchlight loads andI low compression pressures.Variation of theV compression is particularly detrimental, however, inthe case of. engines eperating on producer gas, or similar gas of 'lowor variable thermal-value. Such gases require high compression to insurethorough and prompt ignition, or even to insure ignition at all.` If thefengine hel regulated by varying the amount of fluid taken into thejcylinder, it may eas/ily, and frequentlyl does, happen, that at lightloads and 10Wv compression pressures, ignition is uncertain o r failsaltoge t'her. .It is of course substantially impracticable to supply aricher mixture to an'enjgine when operating at light load than whenoperating at heavy load, and todo so Would stillfurtherdecrease theefficiency at light loads. The extreme ofvtliis l also, .the gas fromthelproducer is apt to be of especiallylow thermal value, and since theengine is then wilthoutload, usually, and its valve gear is a-dJusted sothat the. compression is low it is often diiiicultito ,start 'an engineoperating-on producer gas.v All of these difficulties We bbviate `bytaking 'into -thezcylindersubstantially the same quantit :of fluid' at'all times, regulation being`e 4fected by varying the richness of thecharge by automaticallyvaryingl the amount ofair admitted, or 4byadmitting and similarly regulating a neutral diluent gas, such asproducts of combustion. The compression is then substantially the sameat all loads. 'To compensate for thevariation in the rate of fiainepropagation With-varying amounts ofair .or-'neutral dilnent gas-in? thecharge,

I l u .E c n c. We automatically vary the point ci ignition tocorrespond with the variation in the amount of diluent. ln this way weare able to employ very high compression pressure atall loads, withresulting gain in economy,

`and to realize nearly the same economy at light loads as at full load.

ln the specication of,`A an application for Letters Patent tiled by G.,M. S. rtait on Get. 31, 1905, Sr. No. 285,245, the difficultiesexperienced in the use, in high compression engines, of fuels which arenot homogeneous as to combustible constituents, are pointed out,particularly the difficulties attending the use in high compressionengines of as con: taining a considerable percentage't hydrogen; thehydrogen being apt to ignite auto- Ajmatically during the compressionstroke,

`thus producing excessive back. pressure against the piston, causing theengine to do negative work and greatly lowering the etl'icieney of theengine. Such trouble is termed ,preignition When using a fuel containingingredients, such asv hydrogen, Which tend to cause preignition, orirregular combustion (as when one or more ingredi- .ents burn largely orentirely before the loads, to avoid variation in the compression withvariation in load or speed, to prevent pre-ignition, to insure completeignition, and to permi. the use of fuel of low and variable thermalvalue, and to make the mechanism by which the above objects areaccomplished,

A simple, compact and efficient.

We 'will now proceed todescribe our invention with reference to theaccompanying drawings, illustrating one form of internal combustionengine embodying our invention.

' In the said drawings: Figure 1 shows a central vertical section of theene-ine on a plane transverse to the crank shaft; Fig. 2 shows a sideview of the engine, a portion of the governor mechanism and associatedparts being shown in section; Fig. 3 shows a front view of the governor;Fig. l shows a detail view of the eccentric, Fig. 5 shows a detail Viewof the governor and eccentric looking from the left of Fig. 2; Fig; 6shows a detail topview of the bell crank and associated parts 'of thegovernor mechanism; Figs;4 'l

and 8 show the application of our invention toa multi-cylinder engine,Fig. 7 showing a 9 if. l 984:5

side view of a` three cylinder engine jnovided with` our improved valvegear and regulatin mechanism.

in the said draw-ings 1 designates the engine cylinder, and 2` thecooling jacket thereof, 3 the piston, 4.- the connecting rod, 5 thecrank and (S the crank shaft; these parts being` all of substantiallycommon const rui tion.

7 designates an admission valve and 8 an exhaust valve. These valves areoperated by a` rocker 9 pivoted at 10 and vibratied by means of a valverod 11 connected to said rocker 9 at 12 and itself actuated by a spring13 and by a cam 14- on a counter shaft, 1.3, said shaft 15 being drivenin the construe` tion shown from the crank shaft (i, by means ofsuitable gearing and a shaft 1G. rlhe particular 'engine shown, issupposed to be of the so called four cycle type, and there` for@ thegearing by which shaft 15 is -driven is of such ratio that shaftI 15revolves at half the speed `of the crank shaft. The rocker 9 alternatelypresses in first one ot' the said valves and` then the other. and isadjustable longitudinally at its pivotal point. l0 .for varying thejtimeof opening and closing of the valves. lts two ends are furher providedwith adjustment' screws 1T by means of which a certain adjustment of theoperation of the ,valves may also be obtained. As will be obvious frominspection of the drawings, the operation of this valve gear is asfollows: In Fig. 1 the parts of the valve gear are shown in the positionoccu` pied near the beginning of the admission stroke, piston 3descending and admission valve 7 being open, the lowest portion ot thecam 14 being opposite the end of the valve rod 11. lWhen the pistonnears the end of its downward stroke, the rise '18 of the cam lllliftsrod 11 somewhat, moving rocker 9 sutiiciently to permit the valveto close. At the beginning of the exhaust:I stroke the rise 19 of thecam moves the valve rod 11 androcker still farther, causing valve 8 toopen and at about the end of the exhaust stroke, the valve rod 11 slipsoi'i' from,

rise 19 to the lowest portion of the cam. causing valve S to close andfalve 7 to open. By adjusting the rocker 9 longitudinally the relativeperiods of opening and closing of the two valves maybe varied, and bymeans of the screws 17 the time of opening and degree of opening of saidvalves may also be varied.

Fuel is supplied to the engine through a pipe 20, which may be providedwith suitable regulating means 21 as indicated in Fig. 2. This pipe maybe considered to be a pipe connected to a gas producer.

22 designates a pipe for supplying air for combustion and also for thedilution of the charge for the purpose of automatic regula` tion. Pipe22 may also have some custom i ary regulating device 23: 22 terminatesin a collar 24v surrounding pipe 20, the

' 27, indicated in dotted lines in Fig. 2, which -port may be understoodto be connected toa source ofsupplyof products of combustion,

such, for example, as the exhaust pipe of the engine. The governor 26not only adjusts Vvalve 2,5, but also controls the operation of the.igniting device, varying the time of ignition to correspond with gvariation in the quality of thegas or the amount of diluent admitted. Wemay, of course use any suitable igniting device, and for purposes ofillustration .have indicateda touch" spark igj niter 31, voperatedbyga'n -eccentric .28 on counter shaft 15. and an eccentric rod 29 andbellcrank 30. To 'vary the time `of ignition, we vary the lead of theeccentric 28 by the direct action of the governor. Without 'limitingourselves vto any kparticular type of governor for thepurpose we' haveindicated a well known combined inertia and centrifu-A gal governor.This governor may be caused to vary the lead of the eccentricvby anysuitable mechanism. InFigs. 1`to"6incl'i isive, we have illustrated onemechanism for .the purpose, applicable principally to single cylinderengines and comprisinga link v.32 connecting the governor weight with anarm. 28a projecting from the eccentric 28. Asv

will be seen, whenY theposition of the'goy;

ernor weight changes, theY angular position of the eccentric 28 withreference to the Shaft` 15, will be changed. In the case of a multi-1ple cylinder engine, we ordinarilyemploy" somewhat different mechanismto vary the advance of the eccentric'sby the .action-.of the governor.The same governor 2,6, which controls the' time of ignition, alsooperated' the valve 24. For this purpose the governor.

weight is connected by me'ans of' a link 33 with a bell cran-k '3,4revolving with thev governor and connected atthe center of rotation to alink 35, itself connected to 'a bell crank 36 and thence b a rod 37tovalve-25.

In the case of a multi-cylinder engine, we customarily employ meanswhereby, by the action of a single governor andthe movement of a singleoperating membe'nthe angular'advance of all of the igniter `eccentriesis varied simultaneously 4and to the same extent.4 'One convenient..means for doing this 1s shown` in Fig- 7. As'there shown, the vgovernoris4 .arranged` to4 move videawah Spiral key ways as-,ffwhiehfthetherefore that longitudinal motien of they shaft. varies the angularadvance of all eccentrics simultaneously and to the same extent. In thisconstriction the carrying wheel of the governor and the several valveoperating cams 1e are connected to the shaft 15.` .through straight 'keyways 39 andy run be-. tween `stationary stops 40 which prevent them frommoving endwise with the shaft.

Themethod of regulating the development of pw'er is as follows:Supposing the'engineto beoperating. under maximum load, valve n 2,5vwill be substantiallv half open as regardspassage of air from pipe 22to pipe 2Q, and a charo'eof maximum richness will 8o erite'r'the enginecylinder during each ad-A` missiolrstroke, and will there be compressed,

ignited, and caused t expand, in the ordi-r .y nary Way. If now the loadon the engine' be reduced, the centrifugal governor 26 will" 85 openVAvalve 25- still farther, admitting more -fairfrompipe 22 to pipe 20,and also opening port 27 `'and admitting products of combustion, whichmingle with the air and gas, dilutingthelatteraind retarding thecombustion of hydrogen similar substances until the final ignition ofthecharge. The total amount of fluid'taken into the' cylinderremainslthesame it will be seen, whatever thev` load, and therefore thecompression is sub- 95 stantially thesame at all loads; but the richnessof the charge will be decreased. The rate of combustion"being therebychanged, the governor 26 automatically advances" the poi-nt of ignitionto compensate for the" de-V 10c creased speed of combustion. Conversely,when the load ou the engine is again incre ed,l thefv automatic governorwillrednce puntfjo'f dil'uent admitted and will v p'sed: rateg ,ofcombustion of the charge. "The 'governor `2 6 also varies the point ofOinitio'n .to Ycorrespond with the change in ra e of yflame propagationthrough the mixture dife to dilutionfof the charge, varyfing the angularadvance ofthe eccentric or eccentritzs28. 'It will beseen therefore,`that bythe action o f the two automatic governing device/s thecharacter of the charge and the point ofignition will be varied to suitthe load on the engine and to maintain constant speed, without ivaryingthe compression.A vWe 'are enabled, therefore, -to em' ploy very highcompressionl at light loads as `well as at intermediate and heavyloads,and

to employ fuelv of low thermal value at all loads, the ignition of suchfuel being rela- -tively certainbecause of the very high compressionemployed. This compressionweh prefer to befrom say 91% to 16 atmospheres,`"l25 preferably not below 11 atmospheres'. At `this .highcompression mixtures which can not `be depended upon to ignite at lower`pressures ignite readily.

Producer. gas such as we especiallycori-.130

ignition-5to Acorrespond with the in- 105v eine@ template using has forits principal comlI proportions and are thoroughly mixed voith bustibleconstituent, caibon monoxid; but

. many types 4of producers or generators of fuel gas produce largequantities of hydrogen as Well, giving rise to the preignition troubleabove mentionedwhen the engine operates' with high compression. iVhenthe gas used contains little or no hydrogen, 'we

- commonly einply air' alone as the diluent, it

being understood that any excess of air mixed With the gas above thatrequired for coinbustion is a mere diluentand is substantially neutial.When thel gas used contains considerablequantities of hydrogen or otherreadily igniting gases which 4tend to give rise to preignition troubles,We preferably mix more or less products of combustion with the air. Suchproducts of combustion may be drawn from theexliau'st pipe of theengine, or from thestaclr of any convenient furnace orthe like, and arepreferably cooled before -being mixed With the air and gas, von accountot' the greater density at low temperature. The specilicheat, by volume,of products of combustion is relatively high, ascompared' with air, andsuch products. exert a marked influence tending to hold back theignition of hydrogen and like constituents which tend to igniteprematurely under the conditions cylinder during compression; suchholding back being due, probably, in great measure to the Vpresence ofconsiderable quantities/ of carbon dioxid inthe products of combustion.By properly diluting the cliai'ge to correspond With the load on theengine, Without varying the amount of the charge, by correspondinglyvarying the point of ignition,

and when necessary holding back theigni tion by employing greater orless quantities of products of combustion in the charge, we are able toinsure proper ignition, Without so much combustion before the pistonreaches the end ofits compression stroke as results in excessive baclpressure on the piston and the doing of negative Work; and thereby weare enabled to'use, at all loads, very cheap fuel gas of low thermalvalue,l or containing considerable proportions of -ingredientshavingwidely different rates of combustion, and are thus enabled toobtain very high coinmercial and thermo-dynamic economy.

Hitherto itlias been generally considered that the effect of products ofcombustion in I the chargey ofaii explosion engine is highlypreiudicial, as tending to make ignition irregular oi' to prevent italtogether, and very often elaborate measures have'been taken to producevery complete scavenging of the cylinder; but We have fou-nd" that the.ob-

jections'heretofore found to be unavoidable or the unintentionalretention of a portion of the products of combustion Within the cylinderdo not apply when the products of;

combustionare used in carefully regulated the entering air and gas, butthat to the contrary very decided advantages result from the propermixing of suitably regulated proportions of products of combustion withthe charge, as before stated.

ln the case of engines which operate by the injection of fuel into thecylinder or combustion chamber of the engine, the products of combustionfor diluting the mixture and retarding combustion will'he introduced,orordinarily, With the entering charge of air.

that we claim. is

l. ln an internal combustion engine, the combination of a combustionchamber, means for supplying thereto a combustible charge and a dilueiitgas, and regulating means controlling botli the supply of dilucnt andignition, and arranged to vary the point of ignition and supply ofdiluent; correspondingly.

2. ln an internal combustion engine, the combination of a combustionchamber, means for supplying thereto a con'ibustible charge and adilueiit andv automatic governing means cbntrolling both the supply ofdiluent and ignition, and arranged to vary the point.

spondingly.

3. In an internal combustion engine, the combination of a combustionchamber, means for supplying thereto a combustible charge and a diluentgas, and aii automatic speed governor controlling both the supply ofdilu cnt and ignition, and arranged to vary the point of ignition andsupply of diluent correspondingly.

et. In. an interna-l combustion engine the combination of a, combustionchamber, means for supplying thereto a coinbustilile charge and productsof combustion, and regulating` means controlling both the supply ofproducts of combustion and ignition, and arranged to vary the point ofignition and lsupply of products of combustion correspondingly. s

5. ln an internal cbmbustion engine, the combination `of a combustionchamber, means for supplyingthereto a combustible charge and products.of combustion, and au- -toniatic governing means controlling both thesupply of -products of ,combustion and ignition, and arranged to varythe point of ignition and supply of products of'coin- `bustioncorrespondingly. l

6. ln an ,internal combustion engine, the combination of ay combustionchamber, means for supplying thereto a eon'ibustible charge and productsof con'ibustion, and an automatic speed governor controlling both thesupply of products of combustion and ignition, and arranged to vary thepoint of ignition and supply of-pioducts of combusion correspondingly.

in an internal combustion engine, the combination of a combustionchamber,

Crt

mixture and alsovamancla dierent-dilut-j ing gas, and regulating meanscontrolling? means for supplying thereto a combustible the supply ofboth. n

means for supplying theneto'a combustible mixture .and also air amil adifferent diluting gas a Valve controlling both the latter, 4ernor for'adjusting said waive;

the supply of 10. In an internal combustion engine, the

combination .of means ifm' :supplylng a comof combustion to en,

trolling such supply yof mr products of combustion, `anni an automaticgovernor for adjusting-said valve.

bustibleV mixture and also air an dioxid to the engine, a -valy suchsupplyof air and carbondioxid, an

span automatic governor for valve. Y v. v

1.2. In an internal combustion engine, the combination of means forsupplying a comi',bustible mixture and a diluent gas .to' the 3 5engine, a valve controlling such supply Vof -diluent gas, ignitingmeans, andautomatic governing means controlling sa'ilvalve and Yignlting means correspondingly. j

13. In an internal'combustion'engine, the 40 combination of .means 'forsupplying a combustible mixture and'a-jdiluent lgas to the engine, a`Valve controlling?suchsuppl)1 of diluent gas, speed goifernoracljustingxbothtsaid va Ve 'and the Apoint of igmtion correspondingly.

V14. In an'internal combustion engine, the

combination'of means for` supplying a combustible mixture and a 'diluentgas to the en ine, ignlting means, a shifting eccentric 50 or 'operatingthe same,V regulating means which shifts saldeccentricto Vary the pointr of ignition, vantmeans' operated by said regulating means for varyingthe supplyof diluent harmo and an :auitaamatic lspeeol govbust-iblemiXtureand also aiirjan vproducts a' valve can; f

,- 'ignition accordingly.- all. In an internal the combination ofmeansfor'suppl a comigniting means, `antifa sin 1eof ignition. v f

1 5; In an internal combustion engine, the combination of a -combustionchamber,

ywith the change in point meansor supplying a combustiblemixture landthereto a combustible mixture and air and a further diluent gas and forvarying the proportion of diluent while maintaining substantially,constant the `,total amount of gas,'and means for compressingthe gas in'saidfchamber Ato between 9% fand 16'atmospheres, approximately, andcausing combus tion thereof. j,

'16. In an internal combustion engine, the

combination of a combustion chamber,v

means forfsupplying thereto La combustible :mixture and air and afurther-diluent gas,

means for compressing the gasin said chamber 'to between :and 16atmospheres :1pv 'proximately, and for causin combustion thereof, andlautomatic regu ating means tcomprlsing means for Vvarying the propor-'tion of diluent and for 'varying the point of 17.111 an internalcombustion engine, the

combinationV of a combustion chamber,

means for supplying thereto fuel and combastion-supporting 'gas- 'andlproducts of combustion, means for cempressng the contentsA of `thechamber, vand for causing the ofalln'oductsA of combustion and tionthereo,-. and automatic gmeans comprising means for va rmportin forvarying. sponolingly;l

18. In K an internal combustin engine, k the e 'point of ignition corre-'combination of a combustion' "chamber,

mea/ns for. supplying thereto fuel and comlbus'tion supportingl gas andcarbon dioxid,

means for com'ressing the contents of the chambenfanfl or causing'lgmtlon thereof, and automatlc regulatmg means compus- '95 ingmeans-for- Varying'the proportion of I carbon dioxid and for varying'thepoint of ignitio'n correspondingly. l

In testlmony 4whereof-,We hereunto ,atix

our'signaturesin the'presence of two wit- GODFREY-M. SuTAIT.

, CARLETON ELLIS.

Witnesses:

I-I.v M. MARBLE, FLETGHEn P. SCOFInLp.

